From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Mon, 28 Apr 2014 10:58:58 +0000 (+0300)
Subject: staging: lustre: integer overflow in obd_ioctl_is_invalid()
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=ee02eb4ae43b3b65cbf4c49c6915fe9d63aac970;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

staging: lustre: integer overflow in obd_ioctl_is_invalid()

The obd_ioctl_getdata() function caps "data->ioc_len" at
OBD_MAX_IOCTL_BUFFER and then calls this obd_ioctl_is_invalid() to check
that the other values inside data are valid.

There are several lengths inside data but when they are added together
they must not be larger than "data->ioc_len".  The checks against
"(data->ioc_inllen1 > (1<<30))" are supposed to ensure that the addition
does not have an integer overflow.  But "(1<<30) * 4" actually can
overflow 32 bits, so the checks are insufficient.

I have changed it to "> OBD_MAX_IOCTL_BUFFER" instead.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/staging/lustre/lustre/include/lustre_lib.h b/drivers/staging/lustre/lustre/include/lustre_lib.h
index bdc981214805..3c26bbdc44b7 100644
--- a/drivers/staging/lustre/lustre/include/lustre_lib.h
+++ b/drivers/staging/lustre/lustre/include/lustre_lib.h
@@ -179,24 +179,25 @@ static inline int obd_ioctl_packlen(struct obd_ioctl_data *data)
 
 static inline int obd_ioctl_is_invalid(struct obd_ioctl_data *data)
 {
-	if (data->ioc_len > (1<<30)) {
-		CERROR("OBD ioctl: ioc_len larger than 1<<30\n");
+	if (data->ioc_len > OBD_MAX_IOCTL_BUFFER) {
+		CERROR("OBD ioctl: ioc_len larger than %d\n",
+		       OBD_MAX_IOCTL_BUFFER);
 		return 1;
 	}
-	if (data->ioc_inllen1 > (1<<30)) {
-		CERROR("OBD ioctl: ioc_inllen1 larger than 1<<30\n");
+	if (data->ioc_inllen1 > OBD_MAX_IOCTL_BUFFER) {
+		CERROR("OBD ioctl: ioc_inllen1 larger than ioc_len\n");
 		return 1;
 	}
-	if (data->ioc_inllen2 > (1<<30)) {
-		CERROR("OBD ioctl: ioc_inllen2 larger than 1<<30\n");
+	if (data->ioc_inllen2 > OBD_MAX_IOCTL_BUFFER) {
+		CERROR("OBD ioctl: ioc_inllen2 larger than ioc_len\n");
 		return 1;
 	}
-	if (data->ioc_inllen3 > (1<<30)) {
-		CERROR("OBD ioctl: ioc_inllen3 larger than 1<<30\n");
+	if (data->ioc_inllen3 > OBD_MAX_IOCTL_BUFFER) {
+		CERROR("OBD ioctl: ioc_inllen3 larger than ioc_len\n");
 		return 1;
 	}
-	if (data->ioc_inllen4 > (1<<30)) {
-		CERROR("OBD ioctl: ioc_inllen4 larger than 1<<30\n");
+	if (data->ioc_inllen4 > OBD_MAX_IOCTL_BUFFER) {
+		CERROR("OBD ioctl: ioc_inllen4 larger than ioc_len\n");
 		return 1;
 	}
 	if (data->ioc_inlbuf1 && !data->ioc_inllen1) {